Improving usability in pan gateways by means of a novel Bluetooth pairing method

Abstract

This thesis investigates the usability issues surrounding an implementation of the Personal Area Network (PAN) Gateway, a new concept in mobile communications. The PAN Gateway device consists of a GSM/GPRS modem and a Bluetooth modem. The Bluetooth modem is used to link mobile devices to form a PAN and the GSM/GPRS modem is used to link the PAN to external networks. The possible Man Machine Interfaces for the PAN Gateway are discussed together with the usability of existing Bluetooth devices. A weakness was discovered in the usability and security of Bluetooth Pairing in existing mobile devices and this led to the development of the "Touch and Find" system and the Pairing Link Protocol. The "Touch and Find" system interacts with the Bluetooth stack and allows simple, intuitive pairing of Bluetooth devices via a serial link. A full duplex serial link was implemented using simple electrical contacts to provide the link. Inductive coupling and infrared solutions were also developed. The Pairing Link Protocol specifies the signal flow for the "Touch and Find" process. The "Touch and Find" system that was implemented using simple electrical contacts shows how simple Bluetooth pairing can be. Pairing is simply carried out by briefly touching together the devices to be paired. The "Touch and Find" system was implemented in C on Borland C++ and used in conjunction with TTPCom's Bluetooth development system, which consists of a "Mad Cow" evaluation board and Genie - a Bluetooth development tool. The research carried out demonstrates the feasibility of the "Touch and Find" system over a variety of physical mediums. The system greatly improves the usability of Bluetooth Pairing, thus improving the "Out of Box" experience. It is likely that the Inductive solution can be extended to enable battery charging across the "Touch and Find" Inductive interface, further enhancing the "value added" capabilities of this system.